Indispensable in laser-processing applications is an accurate and efficient delivery of light energy to process points. For mass production, multi-beam parallel processing is a must to gain high throughput. Diffractive optics is a competitive and cost-effective solution to achieve these goals. A diffractive optical element (DOE) is able to offer various light-control functions such as focusing, splitting and shaping according to the user’s requests. These elements can be utilized in a compact and convenient optical system. Thus laser-processing technologies using diffractive optics can be easily brought into manufacturing settings. We present four laser-based processes, each of which adopts diffractive optics in a distinctive way. They are 1) laser drilling of silicon wafers using a diffractive array illuminator to form microcavities for inkjet printers, 2) laser cutting of metal films using a diffractive focusator to produce liquid-crystal display panels for mobile phones, 3) laser soldering of quartz oscillators using a diffractive beam duplicator onto printed circuits set in wristwatches, and 4) laser sealing of packages using diffraction patterns to house electronic components therein. Some of these processes are at work routinely in our manufacturing plants.